Synergistic Dual-Additive Electrolyte Enables Practical Lithium-Metal Batteries

A rechargeable Li metal anode coupled with a high-voltage cathode is a promising approach to high-energy-density batteries exceeding 300 Wh kg(-1). Reported here is an advanced dual-additive electrolyte containing a unique solvation structure and it comprises a tris(pentafluorophenyl)borane additive and LiNO3 in a carbonate-based electrolyte. This system generates a robust outer Li2O solid electrolyte interface and F- and B-containing conformal cathode electrolyte interphase. The resulting stable ion transport kinetics enables excellent cycling of Li/LiNi0.8Mn0.1Co0.1O2 for 140 cycles with 80 % capacity retention under highly challenging conditions (approximate to 295.1 Wh kg(-1) at cell-level). The electrolyte also exhibits high cycling stability for a 4.6 V LiCoO2 (160 cycles with 89.8 % capacity retention) cathode and 4.95 V LiNi0.5Mn1.5O4 cathode.